Microsomal triglyceride transfer protein (MTP) catalyzes the transport of triglyceride, cholesteryl ester, and phospholipids. It has been implicated as a probable agent in the assembly of Apo B-containing lipoproteins, biomolecules which contribute to the formation of atherosclerotic lesions. See European Patent application publication no. 0 643 057 A1, European Patent application publication no. 0 584 446 A2, and Wetterau et al., Science, 258, 999-1001, (1992). Compounds which inhibit MTP and/or otherwise inhibit Apo B secretion are, therefore, useful in the treatment of atherosclerosis. Such compounds are also useful in the treatment of other diseases or conditions in which, by inhibiting MTP and/or Apo B secretion, serum cholesterol and triglyceride levels can be reduced. Such conditions include hypercholesterolemia, hypertriglyceridemia, pancreatitis, and obesity; and hypercholesterolemia, hypertriglyceridemia, and hyperlipidemia associated with pancreatitis, obesity, and diabetes.